22 interesting facts about gentoo penguins

25/04/2024

From pink poo to catastrophic moulting, these are the most interesting facts about gentoo penguins.

Unsurprisingly, we at the UK Antarctic Heritage Trust have quite an affinity towards gentoo penguins. They are our favourite species of penguin partly due to their bright orange beaks, white-feather bonnets and rosy feet. However, it’s primarily because there are over 1,000 of the waddling acrobats residing at our flagship base, Port Lockroy on Goudier Island. They can also be found at nearby Damoy or further south at Detaille as well as many other spots along the Antarctic Peninsula. 

As such, we’ve learned quite a few interesting facts about gentoo penguins over the years, the best of which we share below to celebrate this year’s World Penguin Day.

Interesting facts about gentoo penguins

1. The colony at Port Lockroy is home to over 1,000 gentoo penguins and has a special place in hearts. Every year, we send a team to the base to run the world’s southernmost post office and museum there.

2. We’ve been surveying the colony at Port Lockroy since 1996. It has run every year except when the base was closed due to the pandemic in 2020/21.

A wildlife monitor surveys the penguins at Port Lockroy (Credit: UKAHT/Jérôme Viard)

3. Gentoo penguins are found on the Antarctic Peninsula, Subantarctic islands, southern continental coasts and islands, and several South Atlantic islands.

4. Gentoo penguins are the third largest penguin, after the emperor and king.

5. Adult gentoo penguins grow to between 70-90cm (27-35in) tall and weigh between 4.5-8.5kg (10-19lb).

6. Once a year, gentoo penguins undergo "catastrophic moulting" where they replace their entire plumage of feathers by shedding the old feathers and growing new ones. At one point during this moult, the penguins will have two layers of feathers as the new ones begin to emerge while the old ones remain attached.

A gentoo going through "catastrophic moulting" (Credit: UKAHT/Jérôme Viard)

7. It's estimated there are around 774,000 adult gentoo penguins in the wild.

8. As such, gentoo penguins are classified as ‘stable’ and of ‘Least Concern’ (LC) on the IUCN Red List of vulnerable species.

9. The Latin name for Gentoo penguins is Pygoscelis papua which means brush-tailed.

10. Gentoos have the most prominent tail of all penguins – it sticks out behind them and sweep from side to side as they walk.

The study area at Port Lockroy (Credit: UKAHT/Jérôme Viard)

11. Gentoo penguins are the world’s fastest underwater birds. They can reach speeds up to 36kmph (22mph) per hour. 

12. Gentoos can dive to depths of up to 170-200m (560-660ft).

13. During deep dives, gentoo penguins reduce their heart rate from their usual 80-100 beats per minute (bpm) down to 20bpm.

14. Gentoo penguins usually mate with the same partner every year and rear two chicks on nests made of pebbles and feathers.

A gentoo sits on its egg (Credit: UKAHT/Jérôme Viard)

15. Gentoos build their nests from pebbles and moulted feathers.

16. Gentoos lay two eggs during the austral summer. In southern locations, the first and second-born chicks are equally likely to survive but the second chick to hatch in more northerly islands often dies.

17. After the eggs hatch, both parents forage and feed the young chicks, who remain in the nest for approximately one month. The chicks then form crèches (groups) with other penguins in their colony for protection while their parents are away fishing.

A nesting gentoo surrounded by pink guano (Credit: UKAHT/Jérôme Viard)

18. Gentoos feed on crustaceans – such as krill – as well as fish and squid. It is krill that can cause a gentoo’s guano (poo) to appear pink.

19. Penguins have a fast metabolism and poop every 20 minutes. Jets of guano can travel as far as 1.2 metres (3.9ft)!

Penguins have a fast metabolism (Credit: UKAHT/Jérôme Viard)

20. Gentoo penguins are closely related to Adélies and chinstraps but have distinctive orange-red bills and feet.

21. Gentoo penguins live for around 15 to 20 years in the wild.

22. Occasionally, gentoo penguins are born with a rare genetic condition called leucism which, due to a lack of pigmentation, causes the penguin to be white. While it does them no harm, it can cause them to be more vulnerable to predators as they can be more easily seen.

A leucistic gentoo penguin at Port Lockroy (Credit: UKAHT/Jérôme Viard)